Arrangement for manoeuvring a boat

An arrangement for manoeuvring a floating vessel with reduced need for or without the need for rudder deflection, the vessel towing a load, such as a trawl, comprising at least two tow lines coupled to a respective winch on board said vessel, and at least two blocks at the aft end of the vessel, over which a respective tow line extends, at least one of the blocks being moveable transverse to the longitudinal axis of the vessel and/or longitudinally of the vessel;

• the position of the moveable block(s) defining a point of attack for a tension force from the tow line, wherein the arrangement further comprises a manoeuvring unit adapted to receive input from a navigation system and being coupled to an actuator moving said block(s) transverse of the longitudinal axis of the vessel and/or longitudinally of the vessel, in order to change the moment of force of the tension force (W′) about a rotational centre of the vessel, and the manoeuvring unit being equipped with a calculation unit which detects the tension force of the tow line(s) and calculates the moment of force from the tension force on the vessel, whereby the manoeuvring unit is adapted to use a change in said moment of force to manoeuvre the vessel, the manoeuvring unit being coupled to at least one of said winches, and being adapted to reel out or in tow line to reduce or increase tension in the tow line coupled to said winch, and the manoeuvring unit being coupled to a rudder on the vessel, so that the manoeuvring unit, if required, initiates a rudder deflection to achieve a desired course for the vessel.

A method of manoeuvring a floating vessel with reduced need for or without the need for rudder deflection, whereby the vessel is towing a load, such as a trawl, and where at least two tow lines coupled to a respective winch on board said vessel extend over at least two blocks at the aft end of the vessel, at least one of the block(s) being moveable transverse of the longitudinal axis of the vessel and/or longitudinally of the vessel;

• the moveable block defining a point of attack for a tension force from the tow line, wherein the vessel includes a manoeuvring unit coupled to receive input from a navigation system, one of these inputs being a desired heading for the vessel;
• the manoeuvring unit comprising a calculation unit, which recalculates a change of heading to a moment of force, which will cause the necessary change of heading to achieve the desired heading, that the tension force from the tow line is calculated, that a transverse or longitudinal movement of at least one of the block(s), which results in the desired moment of force, is calculated, and that the manoeuvring unit sends a signal to an actuator, which moves the block a distance, which provides the desired moment of force, and that the manoeuvring unit is coupled to at least one of the winches to provide for reeling out or in tow line to reduce or increase tension in the tow line—coupled to said winch, and that the manoeuvring unit further is coupled to a rudder on the vessel to, if required, provide a rudder deflection to achieve the desired heading and/or course over ground for the vessel.